Airplane
You should book airplane as early as possible! The number of students come to BCF is said to be more than 10,000 so it is foreseeable that the price soon rises. The nearest airport is Boston Logan International Airport (which is famous these days with a naked man fell from the ceiling of women's bathroom lol). Look up your airplane in Expedia or something. The ideal is that you arrive Boston on Thursday, and you'll get plenty of time to prepare.If you live in the United States, you ca also use Megabus. I do not know well about it though.
Lodging
Unfortunately hotels around the Boston Convention & Exhibition Center are really expensive and cost you more than $100 each night. If you want to book these hotels to save time, you have an option to book these hotels with some of your friends.Do not forget to book hotels earlier also.I booked a motel room around Watertown and it costed me about $70 each night. If you are able to book hotel around the Center, I recommend to do so, because the price is almost same if you book them with your friends. Moreover lodging in motel was really time-consuming for me. You have to take 1 hour to go to the Center, with transferring from bus to train.
If you book hostel, you can save money at the same time you can share your info with your roommate. The demerit is that you will be unable to relax or focus on your task in those situation. And sometimes the info you shared with roommates are worthless for you.
It is announced by CFN that you should avoid lodging around Orange line and some particular areas. Check out the website of CFN.